Personalization markers can be used with online map services (e.g., Google Earth™) to highlight geographic locations in imagery provided by the online map services. Users can add a variety of personalization markers to map imagery, including placemarks (i.e., for highlighting a geographic location), image overlays, paths, polygons (i.e., for selecting a geographic area) and network links (e.g., hyperlinks). These personalization markers can be shared in online communities and other forums, where users can, for example, manually download image overlays containing personalization markers of other users and incorporate the overlay into the current imagery.
If a user uses a particular map service for several years, and in several different settings incrementally adds personalization markers, the user's view of the imagery can become “messy” and difficult to use. Additionally, users with similar personalization markers, such as partially geographically overlapping or semantically overlapping (e.g., jazz festivals in Ireland and jazz festivals in Norway) markers, are likely to have a common interest. When online communities grow to tens of millions of users it will become increasingly harder for users to manually find interesting sets of personalization markers in the absence of automated search tools.